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arXiv · 1702.06489

BCFT and OSFT moduli: an exact perturbative comparison

Pier Vittorio Larocca·Carlo Maccaferri
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Abstract

Starting from the pseudo-${\cal B}_0$ gauge solution for marginal deformations in OSFT, we analytically compute the relation between the perturbative deformation parameter $\tildeλ$ in the solution and the BCFT marginal parameter $λ$, up to fifth order, by evaluating the Ellwood invariants. We observe that the microscopic reason why $\tildeλ$ and $λ$ are different is that the OSFT propagator renormalizes contact term divergences differently from the contour deformation used in BCFT

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Pier Vittorio Larocca, Carlo Maccaferri. 2017-11-28. BCFT and OSFT moduli: an exact perturbative comparison. https://doi.org/10.1140/epjc%2Fs10052-017-5379-3

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